As indeno[2,1-c]quinoline derivatives, for example, compounds substituted at 6-position by a piperazinyl group described in Med. Chem. Res., 3, 44-51 (1993) are known. Although the document discloses antiserotonin activities thereof, antitumor activities of the compounds are in no way reported and described in the document. The antitumor activities of the condensed-indan derivatives of the invention are, hence, unknown.
It is an object of the invention to provide compounds which have excellent antitumor activities and are useful as medicament for treatment of tumor.